Following is the financial information of Optimum Solvers Inc. for the last financial year: Operating Income Sales Average Operating Assets 219,000 $2,190,000 $730,000 Calculate its margin ratio and turnover ratio. a. Margin ratio is 10%; turnover ratio is 3 b. Margin ratio is 11%; turnover ratio is 3 c. Margin ratio is 11%; turnover ratio is 4 d. Margin ratio is 10%; turnover ratio is 4